See, I can buy that type of marketing campaign for the anticipated sequel of an established franchise, but I would think a new property altogether needs a bit more buildup.
I think that's because we've been conditioned to expect long run-ups to game releases.
I'm willing to bet BioWare could reveal a brand new franchise one month before release, and it would be all the marketing time they'd need. Interviews already lined up, gameplay videos done, magazine covers ready, and NDA'd journalists already having hands-on time with it. If you wanted to generate some pre-reveal hype, have something like, "BIOWARE TO ANNOUNCE THEIR NEW RPG ON...." with countdown timers, etc. so everyone tunes in on "The Day".
The moment a AAA developer like BioWare announces a new game, it's front page news on every gaming site. They'd be tripping over themselves to post every scrap of information they could get on it for those 30 days. And more, it's not as though everything suddenly stops the day of release. There's all the gamer reviews/let's plays that come in, word of mouth, and so on.